package Dome4;

public class Text4 {
    public static void main(String[] args) {
      /*  String s1 = "wang";
        String s2 = "HELLO";
// 小写转大写
        System.out.println(s1.toUpperCase());
// 大写转小写
        System.out.println(s2.toLowerCase());*/
        String s = String.format("%d-%d-%d", 2002, 5,24);
        System.out.println(s);
    }
}
